Friday, August 21, 2009

Cyclist PalsyMany cyclists' first bout with injury on the bike is usually one of the three points of connection between man and machine: the hands, the gluts, and feet. Today we will look at the hands which often can give rider's pain as well as numbness or worse yet muscle weakness. The last thing we need is a decrease in the ability to hold on to the handle bars and get feedback from the road. One common injury is Cyclist's Palsy or Ulnar Neuropathy , which is an injury to the ulnar nerve. We can take a closer look at the anatomy and the mechanism of injury in an effort to better understand the problem. Lastly, we will look at various types of situations where this problem can arise and the solutions to them.If we look at the anatomy of the hand we see that the ulnar nerve runs along the anterior (front) ulnar(pinky) side of the hand. The ulnar nerve supplies motor and sensory supply from the medial (inside) side of the hand to the pinky finger and part of the ring finger. When the ulnar nerve enters the wrist it goes through Guyon's tunnel, which is made up of two bones called the pisiform and hamate, which are connected by ligaments. One important thing to note is that this is a tight area, so once an injury occurs and you get inflammation to the area, and it will be more difficult to heal due to the repetitive stress and pressure. In addition, the nerve gives off sensory branches before it enters the tunnel of Guyon. This is important because the branches create two areas of possible injury. One being the sensory branch which if injured, gives you numbness and tingling. Second, the motor branch, which if injured would cause a loss of muscle strength. You can have an injury that affects one or both branches. Therefore, some people have only numbness, tingling, and pain, while others have motor weakness and some lucky patients have both.So how does the ulnar nerve get injured? First and most common is a poor bike fit with too much weight on the front of the hands and an increase in the angle at the wrist closing down on the tunnel of Guyon and compressing the nerve. Other factors to consider are the length of saddle time; for example, touring cyclists are in the saddle for an extended amount of time and are exposing the area to more pressure, and vibration. Multi-day road races also have longer saddle times and usually more overall training. Lastly, for road cyclists, riding on rough terrain means that there are a number of bumps, increased vibration on the hands, and this can add but not solely cause an injury to the nerve. The constant vibration and pressure on the ulnar nerve can cause Neuropraxia which is a disruption of the outer layer of the nerve and the worst cases cause an interruption of the fibers of the nerve, known as Axonotmesis. Thereafter, you then can get inflammation at the site of inury, which causes an increase in pressure on the nerve at the tunnel. In its worst case, it can potentially lead to surgical decompression. I have also found that some of the amateur cyclists' day jobs can cause a constant irritation of the tendons in the wrist which may increase the inflammation and delay healing of the ulnar nerve. So how do you know if you have cyclist palsy? (ulnar neuropathy). Some patients will get a pins and needle sensation or numbness of the pinky and part of the ring finger. Others may get weakness in the pinky and ring finger and may feel a decrease in their grip strength. You can also look at the muscles of the hand for any wasting or decrease of muscle tone between and around the two fingers. Another severe case of nerve disturbance is where you can have a claw like appearance of the pinky finger due to the damage of the ulnar nerve supplying innervation to certain muscles and leaving others unopposed, which can cause deformity. Pain is also associated with this problem and may occur with severe or mild cases.So what do you do if you fall victim to this nasty little injury. You have to correct the problem! First, you have to make sure your fit is "spot on," or better yet get a bike fitting by an expert. Here are some tips one should adhere by in order to avoid injury or inflammation. You should avoid holding all your weight on the hand and wrist, paying special attention to the fact that the nose of the saddle is not slanted forward. If you happen to feel upper body fatigue in your shoulders and triceps muscles when riding, then you are supporting too much weight with your upper body. The next thing I recommend is rest! This is something no one wants to do whether you're a pro athlete or amateur cyclist. If you are an amateur rider it is essential to get to some rest off the bike. At a minimum you should decrease the volume and work and slowly go back up in an effort to give tissues time to heal. The next question I frequently get asked is how long should the rest be. This one is virtually impossible for me to determine without seeing the cyclist, the bike, and riding biomechanics. My advice is to work with someone who has treated these types of conditions before and can properly guide you. Another tip would be to change to a recumbent bike at the gym. During this healing time make sure you are conscious of how you use your hands and wrists, in terms of decreasing repetitive movements or continued flexion and extension of the wrist. This will only make the problem worse. The next change you can make is to use bar foam like Fiziks or Aztecs that absorbs vibration and gives some cushion to the wrists and hands. You can try proper fitted gloves with some gel protection, once again to give cushion and decrease vibratory force. The brand Brontrager also makes a bar end plug that helps with road vibration. Watch your hand position, try not to extend the wrist or smash the area around the pisoform bone and change your hand positions as often as possible.So you have made the right changes to your bike and you find its time to see a doctor. You need to find someone with a background in sports or sports medicine. Because there is a chance, due to the lack of their experience, they may not give you the very best care. I will use my clinic as an example as to what procedure I feel should be taken. First, a detailed history and examination is preformed with details about the rider and bike. Most of the time I have the patient bring the bike into the clinic for evaluation, a criteria you may only find in a few clinics. After evaluation, if I suspect ulnar neuropathy I give the patient various options for treatment and recommendations. The hardest part is suggesting they rest, as many people have key events that they have trained for all winter and spring. For those special cases, we try to work out something based on the severity of signs and symptoms. Most case's typically resolve in 3 weeks with no residual issues after that. In other cases, an Electromyograpy (EMG)/Nerve Conduciton Velocity (NCV) test can be done in order to test the nerve and muscles of the hand to determine the extent of the injury. Some of my colleagues usually prescribe NSAIDS to decrease the inflammation, which works very well. I recommend aggressive treatment to the areas of injury with the use of Ice and heat for home care. In the clinic we will use some manipulation and joint mobilization techinques of the wrist in order to maintain proper biomechanics and decrease the chance of other issues like tendonitis and scar tissue formation. We will also use other modalities such as electric stimulation, ultrasound, low level laser, and soft tissue techniques.There are other less conservative measures you can take such as injection of a steroid to the area of inflammation. I do not recommend this because we have found that it causes more problems. Although I have used a modality called Intophoresis, which is a way to get anti-inflammatory medications into the tissue through electrical impulses. This is done without puncturing the tissue and I have had better results. I always give home care instructions that included some basic stretching and rehabilitative exercises. In this case, self massage to prevent adhesions from forming in the area and proper use of ice and heat. Some people have also used vitamin B6 to help; however, all of the research I have read was based on carpal tunnel not ulnar neuropathy. B6 is an inexpensive vitamin and the adequate daily intake will not cause any tissue damage. An adequate dosage is around 250mg during treatment, which may be of some benefit.Lastly, I find that most patients wait too long to receive a consultation. Do not wait! The earlier we start treatment the better. In addition, follow the 10% rule of cycling so your body's muscles, joints, and tendons have time to adapt to the workout. Never do a hard or long workout with new equipment, otherwise, you're kind of asking for it! Small changes or postitional errors can make big problems for the cyclist. In conclusion, your body adapts and makes small pshysiological changes so that over time it "conforms" to the bike.I also instruct people not to get too depressed about the situation and watch their diet. I find that during the time of injuries, some athletes tend to gain weight and begin making poor food choices. Try using this time to enjoy time with family or friends that may have been neglected due to training and have some fun and begin fresh from your injury, ready to go!

1 comment:

You say most people wait too long to seek treatment. How long is "too long"? If the major treatment is just rest shouldn't the patient just rest from biking for 2-3 weeks and seek a doctor if symptoms don't go away after the?